CVE-2026-23100 mm/hugetlb: fix hugetlb_pmd_shared()

In the Linux kernel, the following vulnerability has been resolved: mm/hugetlb: fix hugetlbpmdshared Patch series "mm/hugetlb: fixes for PMD table sharing incl. using mmugather", v3. One functional fix, one performance regression fix, and two related comment fixes. I cleaned up my prototype I...